The functional source of heat from an LED is primarily from what will be called the “back side” of the assembly—i.e. the location away from the “front side” where the light is emitted. This is quite unlike conventional lighting sources such as incandescent, fluorescent, high intensity discharge, which do not have this division. This division between what will sometimes also be called a “light side” (or “front side”) and a “heat side” (or “back side”) therefore allows a novel approach to capturing the waste heat of lighting systems in a way that is not possible with conventional lighting. Since the heat is concentrated in a location away from the “light side,” the space which is illuminated by the LED can remain relatively unaffected by heat from the LED. The space on the “heat side” of the LED can be at least substantially enclosed for efficient capture of heat. Enclosing the space then allows a novel means of capturing, removing, and potentially repurposing the heat generated by LED or solid-state light operation. The term “LED” is meant to include most if not all lighting uses of light-emitting diodes (LEDs) including but not necessarily limited to semi-conductor LEDs, organic light-emitting diodes (OLEDs), or polymer light-emitting diodes (PLEDs) as sources of illumination. However, the reference to different types of LEDs is not a limitation on the scope of the invention, which is applicable to most if not all solid-state lighting (SSL), which includes the different types of LEDs (e.g., semi-conductor LEDs, OLEDs, PLEDs). SSL refers to light emitted by solid-state electroluminescence.
Buildings and other enclosed spaces are generally equipped with heating and cooling systems in order to maintain the comfort of occupants. In the summer, for example, when the temperature is warmer, the heating and cooling system will cool the building. In addition to the outside temperature, many factors can affect the temperature of an enclosed space. For example, most light fixtures produce some heat from the light source or the electrical system that provides power to the light fixture. Other electrical/electronic components such as computers and processors, lighting controllers, amplification and PA systems, etc., likewise produce heat. The heat from the light fixtures and other components is typically rejected (e.g. radiated or conducted) into the enclosed space, working against the building's cooling system. Consequently, heat from the light fixtures and other components can increase the total cost to cool the building. In addition to being expensive, the energy rejected from lighting systems and other components is usually wasted.
Therefore, an effective way to manage heat in these circumstances could be beneficial. One example could be apparatuses, methods, and systems which allow the use of LED lighting and can be highly beneficial in that they can reduce the burden on HVAC systems by concentrating and exhausting heat outside of conditioned space or directing to other beneficial uses. The embodiments outlined below can also reduce the number and/or size of LED fixtures by increasing LED lumen output.
Lighting fixtures and other electrical/electronic components can also be used in locations without climate control, such as outdoor sporting venues.
Some LEDs can emit light in the infrared (IR) wavelength(s), (e.g., at least some IR wavelength(s) alone or in combination with other wavelength(s), such as visible (VIS) or ultra violet (UV), and thus might be considered to generate heat on the “light side” or “front side” of the LED. However, at least of majority of heat from such an LED is at the “heat side” or “back side” of the LED, so the principles of the invention described herein are applicable to this type of LED also. In these types of locations, adequate heat rejection can be difficult especially when a collection of solid-state electronics is highly concentrated. Solid-state sports lights on high poles are an example of a situation in which providing adequate ambient heat sinking capability can be difficult due to the given the requirements for construction many feet in the air. Fixture size and configuration is constrained due to factors such wind loads and aesthetic considerations as well as the need to limit fixture weight to avoid excessive construction costs. This could lead to inadequate heat sinking capability or performance constraints, and potentially damage or premature failure of lighting or other electrical/electronic components. Therefore, apparatuses, methods, and systems which allow the use of LED lighting for these applications and provide effective heat management can be highly beneficial.
Examples of possible applications include, but are not limited to, illumination of indoor and outdoor spaces or areas. The principles could be applied to light generated by SSL sources for almost any application. Some additional examples include but are not limited to, illumination (including containing IR or UV wavelength(s)) for curing photo-sensitive materials such as in photo lithography. Other illumination or use of light applications are possible.